Cropper

Cropper is a tool to perform perspective crop on an image. Typically when taking a photo of something that is supposed to be rectangular, the image turn out quite different for various reasons. It may look as the first image below, where left and right side clearly are not paralel. Cropper will help you achive the last image below, by letting you define the 4 corners of the puzzle individually.

As illustrated in below video, you drag each of the 4 handles to the approx position of each of the corners. Then you use tha TAB key to zoom to each of the corners and position the handle precisely. Once done you hit OK to see the final result, then SAVE to save the file to your device.

Zooming on devices with touch screen can be a challenge, as your finger will prevent you from position the handle 100% accurate. For this reason, you can tap the handle, then offset your finger and drag the handle from there.

Raketten Cropper is available in Apple Store, Google Play Store and Microsoft Store. It is free to use and require no account setup at all.